10 county-level rules, plus city-specific rules for 8 cities in King County, Washington.
Verified from official government sources
Washington state law (RCW 35.21.830) preempts local rent control in King County and all Washington jurisdictions. Neither King County nor any city within it may cap rent increases. Landlords must follow state notice requirements for rent increases under RCW 59.18.140 (minimum 60 days notice typically, 180 days in some cases).
RCW 35.21.830
RCW 35.21.830 Controls on rent for residential structures — Prohibited — Exceptions. The imposition of controls on rent is of statewide significance and is preempted by the state. No city or town of any class may enact, maintain, or enforce ordinances or other provisions which regulate the amount of rent to be charged for single-family or multiple-unit residential rental structures or sites oth...
Under RCW 59.18.650 (effective 2021), Washington statewide law requires just cause for terminating most month-to-month residential tenancies. King County also enacted Ordinance 19340 extending just-cause protections in unincorporated King County. Landlords must cite a permitted reason and provide proper notice.
Unincorporated King County does not operate a general rental registration program. Landlords must, however, follow Washington state requirements (business license, lead disclosure, landlord-tenant registry on individual notices). Several cities within King County (notably Seattle via RRIO) do require rental registration.
Washington's Residential Landlord-Tenant Act and King County tenant-protection ordinances require landlords to pay relocation assistance when displacing tenants for substantial rehabilitation, demolition, or change of use, with amounts varying by city and tenant income level.
Under RCW 59.18.270, all security and damage deposits collected from King County tenants must be held in a trust account at a Washington financial institution, with the tenant given written notice of the bank's name and address within the lease.
Since 2021, Washington's just-cause statute RCW 59.18.650 prohibits no-fault evictions of month-to-month tenants. Landlords in King County must cite one of sixteen enumerated causes such as nonpayment, lease violation, owner move-in, or substantial rehabilitation.
RCW 59.18.650
RCW 59.18.650 Eviction of tenant, refusal to continue tenancy, end of periodic tenancy — Cause — Notice — Penalties. (Effective until January 1, 2028.) (1)(a) A landlord may not evict a tenant, refuse to continue a tenancy, or end a periodic tenancy except for the causes enumerated in subsection (2) of this section and as otherwise provided in this subsection. (b) If a landlord and tenant enter...
Washington's Residential Landlord-Tenant Act prohibits landlords from passing through new fees during a tenancy that were not disclosed in the original lease, including utility surcharges, trash fees, and capital improvement assessments under RCW 59.18.140.
Washington's Residential Landlord-Tenant Act and Seattle's Renting in Seattle ordinance prohibit landlord harassment of tenants, including utility shutoffs, lockouts, repeated entry without notice, and threats designed to force a tenant to vacate.
RCW 59.18.255 prohibits King County landlords from refusing to rent based on a tenant's lawful source of income, including Section 8 vouchers, Social Security, veterans benefits, child support, and unemployment compensation.
The King County Housing Authority and Seattle Housing Authority jointly administer Section 8 Housing Choice Vouchers across the county. Landlords must accept vouchers under RCW 59.18.255 and follow HUD inspection and rent reasonableness standards.
8 cities in King County have their own rental property rules rules. Each link goes to that city's dedicated page with code citations.
9 verified rules • Just Cause Eviction, No-Fault Evictions
3 verified rules • Just Cause Eviction, Rent Control
3 verified rules • Just Cause Eviction, Rent Control
3 verified rules • Just Cause Eviction, Rent Control
3 verified rules • Just Cause Eviction, Rent Control
3 verified rules • Just Cause Eviction, Rent Control
3 verified rules • Just Cause Eviction, Rent Control
3 verified rules • Just Cause Eviction, Rent Control
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